2 13-1 Changing the Living World Humans use selective breeding, which takes advantage of naturally occurring genetic variation in plants, animals, and other organisms, to pass desired traits to the next generation of organisms.
3 Ex: dog breeding, horse breeding – choose parents for their traits, attempts to make disease resistant plants that have a high production rate
4 Hybridization = crossing dissimilar organisms Inbreeding = continued breeding of individuals with similar characteristics… has resulted in the combination of recessive alleles with genetic defects: weepy eyes in dogs
5 Inbreeding Persian Cat flat face= breathing problems Shar-pei Huge rolls of skin=Skin diseaseBasset houndDroopy, baggy eyes=Prone to eye infection
6 Breeders can increase the genetic variation in a population by inducing mutation which are the ultimate source of genetic variability… use radiation and chemicals.New bacteria – oil-digesting to clean up oil spillsPolyploidy plants – larger and stronger plants
8 13-2 Manipulating DNAScientists use their knowledge of the structure of DNA and its chemical properties to study and change DNA molecules. Different techniques are used to extract DNA from cells, to cut DNA into smaller pieces, to identify the sequence of bases in a DNA molecule, and to make unlimited copies of DNA.
9 Genetic engineering = making changes in the DNA code of a living organism Extract DNA from cellsCutting DNA with restriction enzymesSeparate DNA using gel electrophoresisIdentify the sequence using different dyes that attach to nitrogen basesMake copies using polymerase chain reaction
14 Scientists can synthesize a DNA strand and connect it to a circular DNA molecule known as a plasmid… which can be found naturally in bacteria. This bacteria can then be injected into a plant, and will insert its DNA into the plant.If transformation is successful, the recombinant DNA is integrated into one of the chromosomes of the cell.
15 13-4 Applications of Genetic Engineering Genetic engineering has spurred the growth of biotechnology, which is a new industry that is changing the way we interact with the living world.Humans construct organisms that are transgenic and have genes from other species.Transgenic bacteria are being used to produce insulin, growth hormone, and clotting factor.
16 Transgenic animals: mice, livestock Transgenic plants: 52% of soybeans and 25% corn is transgenic or genetically modified.
17 Clone = a member of a population of genetically identical cells produced from a single cell.